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91.
Sulfonation degree determination of sulfonated polystyrene and the corresponding ionomers are performed by adiabatic bomb calorimeter. The theoretical calculations from the band energies for the combustion enthalpy values (calorific values) and the experimental values are compared, and a linear relation between the values is found. Sulfonation and neutralization processes are examined by elemental sulfur analysis and atomic absorption spectroscopy (AAS). It was obvious that increasing sulfonation degree yields a decrease in the combustion enthalpy values, as it is expected from the theoretical calculations. In addition, metal ion incorporation to the structure deviates the experimental combustion enthalpy values especially for the ionomers which have higher sulfonation degrees. This is due to the formation of a higher degree aggregation. © Wiley Periodicals, Inc. J Appl Polym Sci 100: 4684–4688, 2006  相似文献   
92.
In this work, the effects of shear rate on viscosity of selected pure food grade oils (castor and canola) are investigated. The rheological behavior of castor–canola oil mixture is also studied through modeling the experimental data. The effect of shear rate on the variation of viscosity was clearly observed. Interpretations of the results from rheological models indicate that these food grade oils belong to pseudo‐plastic category. The results also show that among the six used mixing rules, Grunberg–Nissan model seems very well fitted to the experimental data.  相似文献   
93.
An experimental system was developed and tested in order to investigate the exergetic performance of a solar photovoltaic system (PV) assisted earth-to-air heat exchanger (under ground air tunnel) that is used for greenhouse cooling at the Solar Energy Institute, Ege University, Izmir, Turkey. This system was under operational conditions successfully during the 2010 summer cooling season. This paper provides the experimental results obtained between 18th of August and 26th of August of in 2010. Exergy destruction in the system was calculated and presented in this paper using a reference temperature of 15 °C. Results are discussed and interpreted in the paper for various performance metrics, such as the effect of climatic conditions and operating conditions on the system performance. Results show that the system may be satisfactorily used for greenhouse cooling in the Mediterranean and Aegean regions of Turkey.  相似文献   
94.

Geothermal energy is already in the form of heat, and from the thermodynamic point of view, work is more useful than heat because not all heat can be converted to work. Therefore, geothermal resources should be classified according to their exergy, which is a measure of their ability to do work. In recent years there has been a remarkable growth of interest in environmental issues—sustainability and improved management of development in harmony with the environment. Environmental impact assessment is one of the most widely used tools in environmental management. In this study, the environmental and exergetic aspects of geothermal energy, namely the rapid impact assessment matrix method, and, specific exergy index, were studied first. They were then applied to the Tuzla geothermal field in Canakkale and Balcova geothermal field in Izmir, Turkey, respectively. Finally, the results obtained are given and discussed.  相似文献   
95.
牛仔服装的流行始于美国加利福尼亚州,美国人Levi Strauss缝制了第一条牛仔裤,他本人是一位旧金山的巴伐利亚布匹商人.牛仔布一词源于意大利的热那亚,当时的热那亚还是一个独立的共和国,海军势力强大,由于海员的裤子需适用于各种环境,而牛仔裤刚好满足这一要求因此成为热那亚海军的供给.洗涤时,海员们将牛仔裤装在大网袋里拖在舰艇后面冲洗,海水将牛仔裤漂白成泛着白头的蓝色,而手感也变得更加柔软舒适.  相似文献   
96.
A new tetrakis 4‐(2,5‐di‐2‐thiophen‐2‐yl‐pyrrol‐1‐yl) substituted nickel phthalocyanine (NiPc‐SNS) was synthesized and characterized by elemental analysis, Fourier Transform Infrared (FT‐IR), and UV–vis spectroscopies. The electrochemical polymerization of this newly synthesized NiPc‐SNS was performed in dichloromethane (DCM)/tetrabutylammonium perchlorate (TBAP) solvent/electrolyte couple. An insoluble film was deposited on the electrode surface, both during repetitive cycling and constant potential electrolysis at 0.85 V. Resulting polymer film, P(NiPc‐SNS), was characterized utilizing UV–vis and FT‐IR spectroscopic techniques and its electrochemical behavior was investigated via cyclic voltammetry (CV). Spectroelectrochemical behavior of the polymer film on indium tin oxide (ITO) working electrode was investigated by recording the electronic absorption spectra, in situ, in monomer‐free electrolytic solution at different potentials and it is found that the P(NiPc‐SNS) film can be reversibly cycled between 0.0 and 1.1 V and exhibits electrochromic behavior; dark olive green in the neutral and dark blue in the oxidized states with a switching time of 1.98 s. Furthermore, the band gap of P(NiPc‐SNS) was calculated as 2.27 eV from the onset of π–π* transition of the conjugated backbone. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
97.
A parametric study of the effect of reference state on the energy and exergy efficiencies of geothermal district heating systems is presented. In this regard, the work consists of two parts: a modeling study covering energy and exergy analysis and a case study covering the actual system data taken from the Salihli Geothermal District Heating System (SGDHS) in Manisa, Turkey. General energy and exergy analysis of the geothermal district heating systems is introduced along with some thermodynamic performance evaluation parameters. This analysis is then applied to the SGDHS using actual thermodynamic data for its performance evaluation in terms of energy and exergy efficiencies. In addition, a parametric study on the effect of varying dead state properties on the energy and exergy efficiencies of the system that has been conducted to find optimum performance and operating conditions is explained. Two parametric expressions of energy and exergy efficiencies were developed as a function of the reference temperature. Both energy and exergy flow diagrams illustrate and compare results under different conditions. It has been observed that the exergy destructions in the system particularly take place as the exergy of the fluid lost in the heat exchanger, the natural direct discharge of the system (pipeline losses), and the pumps, which account for 31.17%, 8.98%, and 4.27% of the total exergy input to the SGDHS, respectively. For the actual system that is presented, the system energy and exergy efficiencies vary between 0.53 and 0.73 and 0.58 and 0.59, respectively.  相似文献   
98.
Biological treatability of raw and ozonated penicillin formulation effluent   总被引:5,自引:0,他引:5  
In the present study, oxidative pre-treatment of pharmaceutical wastewater originating from the formulation of the penicillin Sultamycillin Tosylate Diydrate via ozonation at varying pH and ozone feed rates was investigated. Biological treatability studies were performed with a synthetic wastewater alone and supplemented with raw and ozonated penicillin formulation effluents. The highest COD (34%) and TOC (24%) removal efficiencies were obtained at pH 11.0, whereas the BOD5 value increased from 16 mg l(-1) to 128 mg l(-1) after 40 min of ozonation, corresponding to an applied ozone dose of 1670 mg l(-1) and 33% relative ozone absorption. The studies showed that no degradation of raw penicillin fraction (30% of total COD) occurred, and degradation of the synthetic wastewater being completely treatable without penicillin addition, was inhibited by 7%. Upon 40 min ozonation, the synthetic wastewater could be completely oxidized and at the same time 35% of ozonated penicillin wastewater removal was obtained. Respirometric studies were conducted in parallel and produced results indicating a 22% decrease in the total oxygen consumption rate established for raw penicillin formulation effluent compared to the results obtained from the aerobic batch reactor. No inhibition of the synthetic fraction was observed for the 40 min-ozonated penicillin formulation effluent, biodegradability of the 60 min-ozonated penicillin effluent decreased possibly due to recalcitrant oxidation product accumulation. The modeling study provided experimental support and information on inhibition kinetics in activated sludge model no. 3 (ASM3) by means of respirometric tests for the first time.  相似文献   
99.
The impact of early therapeutic alliance was examined in 100 clients receiving either individual cognitive- behavioral therapy (CBT) or family therapy for adolescent substance abuse. Observational ratings of adolescent alliance in CBT and adolescent and parent alliance in family therapy were used to predict treatment retention (in CBT only) and outcome (drug use, externalizing, and internalizing symptoms in both conditions) at post and 6-month follow-up. There were no alliance effects in CBT. In family therapy, stronger parent alliance predicted declines in drug use and externalizing. Adolescents with weak early alliances that subsequently improved by midtreatment showed significantly greater reductions in externalizing than adolescents whose alliances declined. Results underscore the need for ongoing developmental calibration of intervention theory and practice for adolescent clinical populations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
The major challenge of the operation of every solar cell based on dye including water splitting solar cell (WSSC) and dye sensitized solar cell (DSSC) is the using organic solvent medium which causes to decompose the solar cell structure, resulting environmental impact. Here, we synthesized and characterized two new ruthenium complexes with nitrogen and oxygen donor ligands for DSSC application which show good stability on TiO2 surface in water solvent. Interestingly, the DSSC based on [Ru(dcbpy)2(DPC)]Cl, where dcbpy = 4,4-dicarboxilic acid 2,2-bipyridin and DPC = diphenylcarbazide, was shown better efficiency in water than methanol dye loading as well as N3 as a benchmark sensitizer in the same condition. The DPC-based exhibited open circuit voltage (Voc) of 0.63 V, short-circuit current density (Jsc) of 2.5 mA/cm2 and fill factor (FF) of 70%, resulting an overall power efficiency of 1.12%. The incident-photon-to-current conversion efficiency (IPCE) value is also reached to 45% for [Ru(dcbpy)2(DPC)]Cl in the same condition It is proposed that the ruthenium complex containing nitrogen and oxygen donor ligands is more stability on TiO2 and prevent the decomposition of TiO2 porous under water solvent condition.  相似文献   
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